Process for treating hydrocarbons



Feb. 6, 1940. I MlLLER ET AL 2,189,016

PROCESS FOR TREATING HYDROCARBONS Original Filed NOV. 13, 1935 INVENTOR. HUGH MILLER JAMES L FARRELL PatentedFeb. 6,1940 1 I 'zgi'same-fj" H w: H iRQ ESSF REA ING n i omnons Hugh Mme m .lames LIFai-reII, Whittenburg, q lTex}; Marjorie;. B.. Farrell, execu t rix of said James L. Farrell, deceased, assignors to Phillips Petroleum Company, ,a. corporation Delaware Continuation of application Serial meta-195, Y November- ,1933. v; This application Ap i '2,

' 1936, Serial 'No. $72,394 I 1 Claim. fwr ee s's) The present invention relates to a process for the pyrogenetic treatmentfof hydrocarbon oils and gases, and is a continuation. of an earlierapplication' for Letters Patentrelating to a Process 7 1 and apparatus for treating hydrocarbons filed November 13-, '1933, by Hugh Miller and James L.

- Farrell, and bearing'the' Serial'Number 697,795.

A general object of the invention is to'ximprov'e the efiiciency of pyrogenetic processes through the increase in cycle time and the shortening'of cleaning periods. Y

Aparticular object of our invention is to inhibit the formation and depositofcarbon in thosepo'r-' tions of the apparatus wherein carbon deposit 1 3 usually occurs. By our invention: this latter object is accomplished whilethe pyrogenetic con- I ditions are maintained at the .optimumifor the various stocks treated;

Other objects and v advantages of- Y new 2 invention will becomeapparent as the following-doe scriptionproceeds. M c.

The accompanying drawing diagrammatically illustrates one form ofwapparatus :for practicing our new invention.

may consist of relativelyheavyv hydrocarbons .which are to be cracked-for theiproduction-of- 2 Referring to the drawing, charging stock-, which motor ,fueL; or hydrocarbons j'ofthe motor ifuel range .or slightly heavier which i: are ,to be] re- 6 formed inorder to increasetheiranti-knock value or hydrocarbon gases. which are to be converted to liquids, isfed through: a pipe. .I: to' 2.. heating coil 2 wherein the-hydrocarbons. are subjected'to the conditions best suited tovthe type conversion desired. After passing throughthe' coil 2 the hot converted material. passes through a pipe. 3

in which is mounted a valve 4' and is discharged" into a chamber orseparator 5. Thevalvel is manipulated to maintain any desired pressure on the material undergoing conversion inthe coil 2 if the operations are'to becarriedl out 'inlliquid' or semi-liquid (phase. If the'oper'ations are to be of the vapor phase type the valve 4 may not; be utilized," XTh'e hot products of conversion whichenter the separator 5, separate into vapor and liquid portions, the'vapors passing from the separator. throuhg a pipe 6. which leads to a fractionating tower 'l where the vapors are subjected toxreflux condensation" and fractionation) 5o Vaporsremaining uncondensed in the tower 1 .pass therefrom; through a.;p pe 8' to treating Fahd/or" condensing equipment, vnot shown. The

condensate which iscollectedin the lower per-- ti'on of the tower l iswithdrawn through a pipe '5 9 and discharged through cooling equipment to apparatus.

' sftorag'e not shown." When the converted mate-; rial has-passed the valve land entered the sepa rator 5-where the initial separationoccurs, the temperatureof the material in the-separator 5" is usually. still suflicientlyhigh so that the conversion reaction will continue until the temperature has been sufficiently reduced ;to-'check; the'reaction.v This additional period of time during which .the hydr'ocarb'on materials'are sub-'- jected vto conversion temperatures, results in mi over-cracking whichis {immediately attended by the formation of excessive" quantities of car-v -b0n' which will deposit in the separator 5 with Y subsequent clogging of the apparatus, resulting in frequent shut-downs for cleaning) Not only are the shut-downs frequent, resulting in shortened cycle time, but the removal'of the carbon deposits are usually attended by considerable diflicu'lty and 'entailconsiderable -added expense. By our invention we overcome these dificulti'es in the fol- 2g I lowing manner. I The heavy-liquid residue whichseparates from the vapors in the separator 5- falls to the bottom of the separator Sand is'withdrawnas rapidly as it collects through a vpipe win which is mounted a valve ll, and'permitted to as *fiOgW into a relatively small-supplementary cham-' ber or keg l2, where a small'poolofv'it is permitted to collect. Liquid from this pool is con tinuously withdrawn through a pipe 13 and valve M by a pump l5 and discharged through a pipe 3 IS inwhich are mounted valves'll and I8 and continuously returned to the keg l2. A circulation usually very rapid in rate is thus set up in the keg l2, which results in coolingthe residue leaving the separator 5 below conversion temthrough a cooling coil 2| by means of suitable 'bran'ch connections 22 and 23 in which are:

mountedvalves 24 and 25--respectively. Ifth'e' cooler Zl'is to'be' used, valves and 25 are opened and valve I' lv closed or partially closed, depending on the amount of coolingdesired, all or part of the residue thus being'dire'cted through the cooler 2 I. An extension of pipe I3 in which is mounted a valve 26 is provided as an additional point of discharge of the residue whenever desirable. v We -have-found in circulating the 5:

AIME 4 I therefrom through the pipe 6. By use of thecir I culating keg l2 We have been enabled to increase the specific gravity of theJr esidue from aivalue of about 1.000 or less to values of approximately 1.2000 or more. with an attendant increasein yield of 'vaporizable material 0 rfrom 1'-' 5%or more. Not onlyis there a reductioniini'the-duan tity of residue but by means of the rapid cooling and agitation, no degradation. of. the quality of the residue occurs. The solubility zofthe resultant: very heavy residue usually being 99.5% or better I in carbon disulfide and carbon tetrachloride and reductionand partial cooling in the transfer linethere is no depositof carbon or coke in the Sep rator 5 foritsattached-equipment. :On the other hand, in the usual methods; of operation not onlyi does carbon deposit in the separator, but the I as quality of the residue is greatly degraded. The

solubility of such residue frequently running less than in carbon disulfide andvery much. less than 95% in carbontetrachloride. i

In other processes it is irequentiythe practice to check the cracking'reaction .byinjecting cooler oil into the hotzmaterial;entering the separator valuable for ,iurther' processing. j Allgthisf is avoided by. our invention, with the additional; advantage that we are' able .to recover *a residue.

of superior quality, such that-it is highly desirable for use as roadoil and asphalt.

It will be apparent of course,that the tar keg l2 may varwidely inits dimensions depending on the capacity of; the conversion still, the quantity of residue made, andotherconditions which may 'vary widely with different processes and modes ofoperation. :In our operations we have most frequentlygused a keg having the approximate dimensions, 6 feet long by 20 inches in. diameter in conjunction with primary-separator usually Brieetin diameterby 20 feet long,

In the operation oi our process, the temperatures used .varywidely depending on the type stocks treated, the pressure conditionsum der which the process is conducted, the type prcductsdfesired, etc. The temperature of the converted material leaving the coil Zis mostirequently between 800"? and 1050" F. may be higher or ,lower; depending. on conditions. Through pressure; reduction and vvaporization in the separator 5 the temperature of the residue which falls to the lower portion cfthe separator 5, is reduced usually to a value between and. 850 F., although; these temperatures are also.

subject to considerable variationdepending upon conditions. By means of the circulation through the keg 12 the temperature oi the residue, is

further reduced to from 550 F. to {Z50 Fpfd e- 2,189,016 I I I v pending upon the amount of external cooling, I I

rate of circulation, original temperature of 'thejf the'v'alve A; and' 55 poundsgauge in the separator residue, etc. I

The pressure conditions may va'ry widely also depending on the type process sed and the'stocks' 5 treated 'In'fivapor phase processes thI' essures. throughout will generally" be from "substantiallyatmospheric to pressures up to pound'sl In" liquid phase process the "pressures are also subject to wide yariation, ranging from" about 50 10 pounds to 3000"pounds or moreinfthe heating coil, usually a decrea'se in pressure in the t i -sepa'ratingfzonestosome lower valuesalthough; it;may be.fdesi;rableat times to maintain the full 0011' pressureihro'ughout the separating zonesQ onespecific example, e'charged a recycle gas'oil of .16.5 A. P..' 'I. gravity" into the coil '2 and' I I 'Ih'ea'tedit was: temperature of 920 ,F. under a} pressure of 350 pounds gauge. C After pressure Y the crackedmaterial entered the' separatorqES- at:

atemperatureiof' 775 F. which fell to 150%?Fiat thebottomiof the'separatori. By. circulating-=1 in the keg i2 without. external cooling-the telll a' peraturexwas reduced :toI-T25" F. 'whichfr'esulted in the productionof; 9.6% resid e vm pecific. gravity of 1.1002,, solubilit j g fo m q 5- andzthe tar' keg'zl2. i a It. can thus ibe readily seen that ourinvention has resulted in a new and=very usefu1iimprove-" menttin t'he art ofipyro'genetic treatment'ofhy: 'drocarbons. We therefore desire to claimall the variations and. modifications of our-(process and apparatus which fall within-sthespirit and scopeofthe appended claim. s

.Weclaimzti w process for: treating hydroca'rbons in I the :thydroca'rbons are subjected to' conversion; conditions in a. heatingizone, and the "efiluent {of-i the. heating .zone passed to a separating chamber where .it. is separated into ivapors ,and'; liquid," comprising maintaining? the separating charnber substantially free Q01: accumulated liquidfgbyiima .mediatelylpassing .the 'liquidto :a supplemental chamberrwherejthe liquid isse'gregated from di'-. I

feet contactuwitl'i r the .efiluent of:- saidheating zone, maintaining a; .poolf'o f ;the liquid in the. supplemental chamber wlthdrawing; liquid? from the supplemental chamber; cooling the with: I

is 2,5 cleaned was found,to contain very little carbon l 

